Electric signal system



(No Model.) a Sheets--Sheet 1.

' L. G. WERNER.

ELECTRIC SIGNAL SYSTEM.

Patented May 3,1898.

Inventor. I lead? C'Weriaen .3 fill? flttorizqy,

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, (No Model.) 3 Sheets-Sheet 2.

' L. O. WERNER.

ELECTRIC SIGNAL SYSTEM.

No. 603,369 Patented May 3,1898.

Witnas'ses:

Louis Werner.

I By kzb Jamal-racy (No Model.) 3 Sheets-Sheet 3.

L.. 0'. WERNER. v ELECTRIC SIGNAL SYSTEM.

No. 603,369. v Patented May a, 1.898

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STATES PAT T OFFICE.

QLOUIS o. WERNER, or BROAD BROOK, oonunoricor.

.ELEG1"RVICZSIGINAL SYSTEM.

' SPECIFICATION forming part of Letters Patent No. 603,369, dated May 3,1898.

Application filed June 12, 1897. Serial No. 640,436. (No model.) I

T 00% whom/it may cancer/1,;

Be it known that I, LOUIS C. WERNER, a citizen of the UnitedStates,residing in Broad Brook, inthe county of Hartford and State ofConnecticut, have inventedcertain new and useful Improvements inElectric Signal Systoms, of which the following is a specification.

This invention relates to electric signal systems, and more particularlyto a system for indicating to a vehicle or train moving along a line ofway its position relatively to a'distant point on the same track andespeciallythe distance between it and the nearest vehicle on such track.

Ordinarily the several component parts of the system will be soorganized as to show, by means of indicators on adjacent Vehicles ortrains, the positions of these vehicles relatively to each otherby'indicating to each variations in the resistance of a circuit there-,between, which variations will be due to the increase or decrease ofthe distance between .the vehicles as they move in'opposite directionsor in the same direction toward'or following each other on thesametrack.

As will be obvious, my invention is in the nature of a safety system bymeans of which the engineer of each train on the same track may at alltimes know or ascertain the position of the nearest train thereto andwhether such adjacent train is approaching toward or receding from it,and hence the system may be used either as a substitute for or as anauxiliary to the usual block systems or interlocking block systemscommonly employed on railways.

As is wen known, the. current flowing through an electricalconductor isproporconductor which is between the two trains as the latter movetoward or from each other.

'- Moreover, if suitable devices beincluded in the circuit on each trainvariations in the strength of the current flowing through the circuitmay be noted, and these variations may be made to serve as a means forcorrespondingly operating an indicator located at p a proper point oneach such train or vehicle.

Thus it will be obvious that by means of suitablesignaling devices inthis circuit, preferably in the form of visual indicators, such asgalvanometers, every change in the positions of two adjacent 'trainsmaybe indicated by reason of the corresponding change in the resistance ofthe conductor extending along the line of the track. In a similar mannerthe distance between any single train or vehicle and a distant point onthe same tracksuch, for instance, as an open switchmay be indicated toan aproaching train by providing at such danger-point or switchsuitablemeans for closing the circuit between the conductor and therails at that point-as, for instance, a circuit-closer operative toclose the circuit at the switch when the latter is thrown open.

Another feature of my invention is the pro- -vision, in connection witha vehicle, of a traveling current-collector supported thereon andadapted to have its position automatically reversed when the movement ofthe vehicle is correspondingly changed, thus obviating the necessity forconstantly looking after the current-collector when a train is movingback and forth on a track or is headed in the opposite direction at theend of a line.

In connection with my improved signal system I also deem it desirable toemploy polechanging switches, by means of which the direotion of travelof the current through any indicator may be reversed when the directionof travel of the vehicle on which such indicator is carried is changed,and while this pole-changing switch may be a hand-operated one it willpreferably be automatic in its action and controlled by the changeinposition of the current-collector.

In the drawings accompanying and forming part of this specification,Figure 1 is a sectional side elevation of a portion of an engine andtender movable along a suitable track and equipped with an indicatoradapted to respond to variations in the resistance of a conductorbetween the engine and a distant point, which conductor extends alongthe line and with which a current-collector on the vehicle makes atraveling contact. Fig. 2 is an enlarged detail end elevation, brokenaway in the center, of a portion of one of the trucks of the vehiclecarrying a pair of current-collectors for making traveling contact witha conductor. Fig. 3 is a side elevation of a portion of the same lookingfrom the left in Fig. 2 and illustrating the different positions whichthe current collector may assume. Fig. 4 is an enlarged detail of theindicator and its connections to a suitable source or sources of energy.Fig. 5 is a similar View of amodified form of indicator and itsconnections. Fig. 6 is a plan of a portion of a roadbed, illustratingthe main line and a closed switch in connection with my system. Fig. 7is a similar view showing the switch open and the circuit closed at theswitch between the rails and the conductor extending therealong. Figs.8, 9, and 10 are diagrammatic views illustrating a section of railwayequipped with my improved safety system and showing the manner in whichthe indicators on two adjacent trains operate under differentconditions.

Similar characters designate like parts in all the figures of thedrawings.

The essential elements of my improved system which distinguish it fromother safety systems heretofore employed for communicating from onemoving train to another or from any distant point to a train approachingthe latter are a line of way, a conductor extending therealong andinsulated from the track thereof, a source of electric energy connectedto send current in either direction through the indicator on thevehicle, a vehicle movable along the track, a current-collector 011 thevehicle for making traveling contact with the conductor, means forclosing the circuit between the indicator and the track at some pointdistant from the vehicle or train, and an electrical indicator on thevehicle and in the circuit of the current-collector, this indicatorbeing preferably a visual one, such as a galvanometer, and adapted toindicate variations in the distance between the vehicle and a distantpoint on the increase or decrease of the length and a correspondingvariation in the resistance of the conductor between the vehicle andthat point.

Reference will first be made to Figs. 1, 2, and 3, in which I haveillustrated one method of making contact between a traveling vehicle anda conductor extending along the line of the track.

In Fig. 1, C designates in a general way the cab of the vehicle ortrain, in which a signaling device or indicator I is stationed, thisindicator being suitably connected with one or more current-collectors,preferably supported on the trucks of the vehicle-as, for example,beneath the tender T, coupled to the engine.

In the preferred construction I provide duplicate ciu'rent-collectors oneach train, one adjacent to each rail of the track, and hence atopposite sides of the tender. These current-collectors may be attachedto the trucks of the vehicle in any usual manner; but in this case Ideem it advantageous to secure them to the trucks in such a manner as tobe capable of adjustment in a vertical direction to bring thecontact-face of the collector into proper working position. Hence I haveshown in the depending arms 2 and 2 of the trucks vertical guideways inwhich slides 3 and 3 are adjustable vertically by means of suitablebolt-andslot connections,(indicated in a general way by 4 and 4'.)

The current-collectors,which are designated in a general way by t and t,are carried by these slides in the present case, and each will embody acarrier-arm pivotally connected with the slide on the vehicle and acontactmaker pivoted to the carrier-arm.

As before stated, the current-collector is intended to be automaticallyreversible and is carried by, and controlled by the reversal of themovement of, the vehicle or train. It comprises, preferably, acarrierarm 5 and a contact-maker 0, in this casein the form of a slidingcontact-shoe, preferably triangular and pivoted to the carrier-arm andadapted to operate therewith as a toggle-joint when the train isreversed. As the two current-collectors on each train are substantiallysimilar in construction and operation,a description of one will sufficefor both, appropriate primemarks being employed to designate thosecorresponding parts of the second or duplicate current-collector notreferred to particularly herein.

The current-collector z! is connected with a spring-pressed carrier 7,pivotally secured to the slide 3, and the carrier-arm of the collectoris preferably spring-pressed also and pivotally secured to the carrier7.

For the purpose of holding the carrier up to its working position astopf) is provided on the slide and is adapted to cooperate with acorresponding stop-arm 8 on the carrier to limit the downward movementof the end of the carrier which. supports the current-collector t. Inorder to permit the upward movement of this carrier, however, it ismounted for oscillation on the slide and is connected thereto at itsopposite end by a spring 10, by which it will be returned to its normalposition after being oscillated to permit the reversal of the positionof the contact-maker G. The carrier-arm 5 is alsomounted foroscillation, it being pivoted to the free end of the carrier '7, so asto be capable of movement to the several positions illustrated in Fig.Springs, such as 12 and 13, may be used also for holding thecontact-maker in its working position, the springs cooperating in thisinstance with a boss or projection 14 on the carrier-arm 5. The movementof the carrier-arm to its opposite positions is limited by suitablestop-facesas, for instance, by those of a stop 15proj ectin g sidewisefrom the carrier 7 and adapted to engage the carrier 5 at oppositeceases- 3 sides ofji'ts axis of oscillation when'saidarm' isin itsrespective opposite posit-ions It will be'noted-that'whenthis arm is notin operation it may'hang loosely and be suspended in 'a substantiallyvertical position.

. I'prefer. to employ a sliding contact-maker instead of a trolley forthe reasonthat a trolley would not oppose sufficient resistance to theconductor when in contact therewith to permit the automatic reversal ofthe current- I use a sliding contact-shoe having a substantially flatcontact-face, and this collector.

shoe may be triangular incross-section, so that any'side of the shoemaybea working face.

When a vehicle is moving to the left, a

seenin Fig. 3, the arm 5 will of course be in this action taking placein opposition to the force of thespring 1 0 and: being due to the pullof" the vehicle. As the, shoe .6 is held tightly against the conductor,the pull of .the

train'results'in a toggling actiontaking place,

which causes the carrier 5 to move to the position illustrated in dottedlines in said figure, and thus automatically assume .a' reversedposition suit-able for the running of the train along the track in theopposite direction.

The conductor a will usuallyzbe a wire of uniform-cross-sectionextending along the track, and it may be mounted in any suitable manner,preferably-within the rails. of a track and adjacent to one of them, asshown in Fig. 2.

Itwill be noticed that the conductor is elevated slightly-abovethewtread of the rails,

this being done to clear switches, 85c. v

In order to facilitate the making of contact between "thecurrent-collector and the .condoctor as the former starts from one endof the line of Way, I may connect'the ends of the conductor to inclinedguides 16, as shown in Fig. 3, the shoe 6 normally hanging in the middleposition illustrated in saidview and being so disposed asto ride up theincline of said guide and onto the conductor on the starting of thevehicle or train.

I have made reference in the preceding decrossings, as at scription tothe use of pole-changing switches for reversing the direction of thecurrent A traveling through the indicators, (which latter will bedescribed hereinafter in detail,)

and these switches are preferably carried by the current-collectors. Inthis instance the current-collector t embodies "in itsconstruction apole changer the fixed contacts of which are mounted on the'carrier 7while the switch arm is movable with a part-of-the 'tery. are shown foreach instrument, theplus-poles of the respective batteries beingconnected swinging member whichforms the carrierarm;5. In thiscase thereare four pairs of fixed contact-arms,tl1e pairs being designated,

respectively, by a, b, d, and e. The pairs at andb are disposedoppositely to those shown at d and'e, and all are constructed as yielding or spring arms, having their inner sides in the path of movement ofthe switch 17. This switch carries thereon two contacts 18, insulatedfrom each other and from the arm .17, bywhich they are supported, thefunction ofthese contacts being to bridge the contact-arms of therespective pairs of springcontacts a and b or d-and e. In order to avoidconfusion, the manner in which these contactarms are Wired up andconnected to the conductor c and the trucks. connectedwith the wiresofthe return-circuit is not illustrated in the detail views, but .isshown clearly in the diagrammatic views Figs. 8, 9, and 10,

from. which the wiring will be obvious. As the bridging-contacts 18 arecarried and swing with the carrier-arm v5, it will be clear. that whenthe contact-shoe. isnot in engagement with the conductor, but hangs inthe central position, (shown in Fig. 3,) both of the circuits at thecontacts a, b, d, and ewill be broken, while'if the shoe is in theposition shownat the right in full lines insaidview contact will be madethroughthe terminals d and e, and ifin-Ihe position shown in dottedlines: atthe left circuit will be vmade at the terminals C6 and b. a

As before stated, the indicator is preferably a visualone, operatingsubstantially on the principleof a galvanometer, and the type. of

instrument which I prefer to employ is shown in Fig. 4, together withthe connections thereto and a source of energy therefor. This indicatoris designated in a general wayby I, and as the construction of agalvanometer is 1 well understood thissignaling device willnot bedescribed in detail. Indications are made by means of the usual pointeror index-finger 'i, this being controlled by the directionand strengthof the current traversing the coils of .the. pointer.; As .these coilsare oppositely wound, the current will traverse them inop-,posite'directions,and hence cause the indexfinger to move toward oneside or the other, as thecase may be. The terminals of :these two coils,only one of which will operate at a time to deflect the needle, areindicated by 20 and 20 and.2l and 21.

The current by. means of which the indicator is operated may be takenfrom any suit able source of energy,whether located on the travelingvehicles or at a distance therefrom; but I prefer-to make use of asource upon each train, preferably in the form of abat- In this case twobatteries 22 and 22 directly to the terminals 20 and 21, respectively,while the minus-poles are connected to the pole-changing switches insuch a manner that current may flow in either direction through thewires which connect with the minus-poles of the batteries and in eitherdirection through the indicator. In order to permit the passage of thereturn current through either of these wires leading to the batteries,it is necessary to make use of two coils for the galvanometer in theconstruction shown in Fig. at, the wires for carrying current beingdesignated, respectively, by 23 and 23 and being connected,respectively, to the terminals 20' and 21 at the indicator and to wiresleading to the batteries 22 and 22 at points behind these batteries.

Between the batteries and the terminals 20 and 21 I interpose in thecircuit switches, such as 24: and 2t, normally closing the eireuitsbetween these batteries and said terminals and adapted to be thrown ontostop points 25 and 25, conductors 27 and 27 being connected with theminus-poles of the batteries.

It will be obvious that when the switches are in the positions shown infull lines in Fig. 4c and a circuit is not completed at the track by theclosure of the circuit between the conductors c and the rails of theline of way the batteries 22 and 22 and the two coils of thegalvanometer will be united in series with one another. IVhen currentfrom another battery on another train passes through the conductors 27or 27 into this indicator, however, one of the batteries of thisindicator will then have no complete circuit therethrough, and theindicator will be operated by the other battery and also by the currentfrom that battery through which current flows from the other train.

In Figs. 8, 9, and 10 I have illustrated dia grannnatieally theoperation of the system under different conditions met with regularly onrailways.

In Fig. 8 two trains are supposed to be approaehin g each other on thesame track, and at the proper distance, which may be the length of oneor more blocks of an ordinary railway, each indicator should show thatthere is another train 011 the same track ahead of it. Thecurrent-collectors on each vehicle make traveling contact with theconductor 0, and all the parts are in the positions to indicate to eachof the two trains the presence of the other when the proper switch 2:1:or 2t is thrown by the engineer, both of the indicators being in closedlocal circuits, in which the two pointers are maintained in theircentral positions by the equal and opposite currents flowing through thetwo coils of each indicator until this is done. It will be noted,however, that while the pointers of both indicators are thus maintainedin their central idle positions until such switch is shifted, yet bothindicators are at all times in condition to cooperate with each otherand to indicate each to the other its own position on the track withrespect to such other train. IVhcn two trains are approaching eachother, as shown in Fig. 8, the switch 24: on one of the trains (in thiscase the one at the right in Fig. 8) is shifted by the engineer, andthereupon a circuit is closed from the rail 0', through conductor 30,contacts e, conductor 31, conductor 27, battery 22, (see also Fig. 4,)switch 2t, and contact 20, through that coil of the galvanomcter withwhich the terminals 20 and 20 are connected, whereupon theindicatorfinger i is thrown to the left by the current traversing suchcoil, and the current passes on through the conductor 23, conductor 27,conductor 32, contacts cl, current-collector and conductor 0, whence itgoes to the opposite eurrent-collector t on the train ahead of it, thecircuit then being through conductor 33 to contacts (Z, conductor 31,conductor 27, and the other indicator, through such indicator, causingthe deflection of the pointer toward the first-mentioned approachingtrain, the current then passing out by way of conductor 27 conductor 35,contacts 6, and conductor 36, back to the rail '1'. Each engineer ofthese trains 110w knows that there is a train ahead of him andapproaching, and hence each will be warned by the indicator to stop histrain in time to avoid a collision. It will be noted that not only isthis the case, but that the amount of deflection of the needle at eachindicator will also show to the engineer how far ahead of him the othertrain is, and the amount of such deflection will be controlled entirelyby the length of that portion of the conductor 0 which is between thecurrent-collectors t and t, and hence by the interval between the trainsthemselves.

In Fig. 9 I have illustrated the operation of the system when two trainsare following each other on the same track. As the circuit through theseveral devices of the system has been traced out with respect to Fig.8, it is not thought necessary to follow it in detail in Fig. 9, but,instead, the course of the current is indicated by arrows. In this vieweorrespending sets of contacts (Z and c are bridged by the pole-changingswitches on each train, this being due to the fact that the trains aretraveling in the same direction on the same track, and hence makingcontact with the conductor 0 in the same manner. In this case also theengineer on the train at the right in said view shifts his switch 2&,which points to the train in the rear, thus closing the cireuit betweenhis own train and that following him, and indicating not only that thereis a train behind him but also the interval between the two trains. Itwill be clear that the circuit completed will indicate to the train inadvance that there is one following it, and also to the second trainthat there is one in advance of it, and also the interval between thetwo trains. As the two trains are following each other, it will not benecessary for them to stop but the second train should own train heshifts theswitch 24:.

proceed cautiously and keep at a sufficient distance in the rear of thefirst train.

It will be seen from the preceding description of the operation of thedevices shown in Figs. 8, 9, and 10 that when a train is going ahead andthe engineer on that train desires to know whether there is a trainahead of him he, always shifts the switch 24, while if his train isgoing ahead and he desires. to know whether there is a train behind himhe always shifts his switch. 24, it being understood, of course, that hewill never shift both switches simultaneously. It, on the other hand,his'train is running backward, the manner in which he operates theseswitches will be exactly reversedthat is to say if he desires to findout whether there is a train in front of the head end of his train hewill shift the switch 24,- while if he desires to know whether there isa train beyond the rear end of his The amou ht of deflection of theindicating-fingers will indicate at all times just what the intervalbetween the two trains is, and will thus enable each engineer to gagethe running of his train accordingly.

v In Fig. 101 have shown the operation of the indicators for the twotrains following each other on the same track and one of which has beenreversed and is running backward. In this case, as the movement of thetrain indicated at the right in said figure is the reverse of that whichit ordinarily would have, the. pointer on the indicator is moved in adirection which is the. opposite of that in which'itwould be deflectedusually, and

hence instead of pointing toward the train following it, it points awayfrom it toward the rear of the train on which it is mounted, thusshowing that there is a train following it. Of course the switch whichwould be shifted by the engineerin this case would be that il-lustratedat 24 instead of the switch 24:. The direction of flow ofv the currentthrough the circuit of theother train is indicatedby arrows in Fig. 10.It will be noted here that the conditions are similar in most respectsto those indicated in Fig; 8, except that the direction ofmovementof'thetrain at the right in Fig. 8 is reversed, and hencedifferent pairs of contacts are bridged by the polechanging switch inFig. 10 from those bridged in Fig. 8. In Fig. 8 the circuit is closedthrough contacts dand. 6', whereas in Fig.

10 there is an open circuit at d and e and the circuit is closedthroughthe pairs of contacts a and b. 1

In all of these diagrammatic views the duplicate current-collectors andpole-changing switches are properly connected with the respectiveindicators, but none of the pairs of contacts is bridged by thepolechanging switches, and the current-collectors are freely suspendedand out of contact with any conductor, and hence there is no circuitthrough these parts.

In Fig. 5 I haveillustrated a modification of the indicator, in whichthe ordinary galvanometer may be employedthat is to say, one having asingle coil and only two terminals for connection with the circuits tothe batteries and thecurrent-collector. The indicator is hererepresented byl and the terminals of .the galvanometer-coil by 20 and21". The batteries 22 and 22, the switches 24 and 24', the stop-points25 and 25, and the conductors 27 27 are the same as in Fig. 4; but theconductors connecting the terminals 20 and 21 with the conductors 27 and27 are not continuous. Insteadv I have illustrated conductors 23 and 23ending in contact-points 40 and 40',controlled by relays 41 and 41, theelectromagnets of which are normally in series with each other and withthe batteries and circuit-breaking switches. The armatures of theserelays are connected by conductors -l2 and 42 to the respectiveterminals 20 and 21 of the indicator, and these armatures, whilenormally attracted by their electromagnets and while normally formingcomplete closed circuits from the batteries through the switchesandthrough conductors 4A and 4st and through the cores of theelectromagnets, the armatures of the relays, and the indicator, areadapted, when released, to be carried by the usual light springs ontothe terminals 40 and 40 to close the circuits through conductors 23" and23'. The normally-closed circuit through the relays is as follows: frombattery 22 to relay 41, through the coils of the relay to conductor 23,through conductor 23" to conductor 27 to battery 22, through battery 22to relay 41, through the coils of this relay to conductor 23', toconductor 27, and back to battery 22. The release of either one of thesearmatures is effected either by shifting one of the switches 2-1l or 24:or else by a current flowing from another train and entering by way ofconductor 27 or 27. Both of the batteries 22 and 22' are of the sameelficiency, and it will be seen that when a current enters either ofthese batteries fromthe outside one of the relayswill be deenergized,owing to the fact that its bat-v tery will then have 'nocircuittherethrough, and the indicator will be operated by one bat-'tery on each train. For example, if current enters the conductor 27 (seeFig.5) from another train while the parts are in the position showninsaid figure there will then be no circuit through the battery 22 andthe armature of the relay 41 will be released and will be carried ontothe contact 40, while the current from'the battery 22 and from thebattery on the other train will energize the elec-. tromagnet 4:1, keepits armature attracted, and will pass through the coils and the core ,ofsaid electromagnet and through the indicator, the return-circuit beingby way of conductors 23"and 27. When the parts are in the positionsshown in this view, there is a conducting-path between the batteries andthe indicator through the cores of the electromagnets; but as thebatteries are disposed in opposition to each other no current flowsthcrethrough, and hence the indicator-hand remains in its normalposition. This construction obviates the necessity of employing adouble-coil galvanometer, as in use the relays will take oppositepositions, and thus, when the circuit passes from the track througheither battery, a return-circuit therefor will be completed at the otherside of the indicator.

It will be noticed that when current enters the conductor 27, Fig. 5,from another train in the manner just referred to the current passingthrough the relay 41 from the battery 22 is augmented by the currentfrom the battery which is left in the circuit on the other train. As thetwo batteries 22 and 22, Fig. 5, are opposed to each other, of coursethe current flowing through and from the battery 22 vill not be able topass through conductor 4t and through the core and the armature of therelay 41 to conductor 42 and through the coil of the galvanometer toconductor 42' and thence to the battery 22. Hence this current from thebattery 22 and from the other train must pass through the coils of theelectromagnet of the relay $1 to conductor 23" and out through conductor27, owing to the fact that instead of the two relays being connected inseries with the batteries 22 and 22, as is the case normally when nocurrent is flowing through the instrument from another train, andinstead of each of such relays receiving the full strength of thecurrent of the two batteries 22 and 22, as when connected in anormally-closed local circuit, the battery 22 is the only one from whichcurrent can pass through the relay 41 when current from another trainenters through the conductor 27; but as both the current from thebattery 22 and the current from the battery on the other train passthrough the coils of the relay etl and out through conductors 23 and 27this current is strong enough when opposed to the current from thebattery 22 to neutralize the latter, and as soon as said battery 22 isneutralized it, having then no complete circuit to traverse, is renderedineffective, and the electromaguet of the relay 41 being deenergized thearmature of said relay is shifted to make circuit at 40, whereupon thecurrent from the battery 22 may divide, part following the originalcourse through the coils of the electromagnet of the relay ll and outthrough conductors 23 and 27, while the other part passes through thecore and armature of the relay 41 and through the indicator and outthrough the armature of the relay 41 to contact 40 and to conductor 23to join the current passing through the latter from the first-describedparallel branch of the circuit.

It has been found by experiment that if the relays are properlyconstructed and the batteries are of equal strength either one of therelays will respond instantaneously to an increase in the current of thebattery to which the other relay is directly connected.

Although my invention primarily is intended as a means for preventingcollisions between trains by signaling to two approaching trains theirrelative positions with respect to each other, yet it is adapted foroperation for preventing any kind of accident which might be due toerrors in the running of trains, in the throwing of switches, &c.

It will be obvious that if the circuit be closed between the rails andthe conductor 0 at any point distant from a train approaching on thetrack a circuit through the indicator on the train may be closed whenthe engineer shifts the proper switch 2% or 24:, as the case may be, andthat the presence of such dangerpoint and its distance will be indicatedto the approaching train, whereupon the engineer will of course take theproper precautions to insure the safety of his train.

In both constructions of the indicator and its operating devices shownherein when the switches 2t and 2% are in their normal positions theindicator-hand is held in its central or normal position in Fig. at byreason of its being within the field of equal and opposite currents andin Fig. 5 owing to the fact that there is no current flowing through theindicator, and in both cases the current of one battery on each train isused to deflect the indicator-hand. Hence in every case when a signal istransmitted there are two batteries in circuit, one on each t ain, andas all of the batteries should be of standard strength the only variablefactor in the circuit at such time is the length, and hence theresistance, of the conductor between the trains.

One manner of indicating danger ahead is illustrated in Figs. 6 and 7,in which a main track and siding are shown, the main track being open inthe former view, while in the latter View the switch is open. As a meansfor signaling to the engineer the approach of his train toward such adanger-point I have shown herein, in connection with the trackrails andswitch-rails, suitable means for operating the latter andcircuit-closing means controlled by the opening of the switch forclosing the circuit at such point to indicate to an approaching trainthat the siding is open and that the main track is not clear.

The track-rails are designated,respectively, by 0' and '1", and thepoint-rails or switch-rails by p and 1). These point-rails may beconnected in any usual manner and operated by any suitableswitch-throwin g means. In this case a switch-lever, which is shown at50, operates a pair of gear-wheels 51 and 52, the latter of which isconnected by means of a crank 53 with the usual switch-rod 54 in suchmanner that when the switclrleveris thrown to open the switch the gearswill be operated, the crank actuated,and the point-rails shifted.

The switch-lever is intended to be locked in its extreme positions andto close the cirposition in orderto prevent tampering with the tracksystem.

As before stated, the visual indicators will not only indicate thepresence of an approaching, following, or receding train, but also thedistance between one train and another train or danger-point, and thisindicator may have thereona'scale showing distancesas, for instance,in'yards or multiples thereofto indicate to the engineer at a glance thedistance between his train and such other point.

I It should beunrlerstood that it will be the duty of. the engineer ofthe train or operator of the vehicle to shift the switches 24 and 24from time to time to determine whether there is any obstruction on thetrack either ahead of his train or vehicle or in the rear thereof.Moreover, a code of signals maybe adopted by means of which theengineers of adjacent trains may indicate to each other the direction inwhich they are moving on the track. For instance, an engineer movingnorth or east may indicate that fact-.byshifting his switch twice fromits normal position, and thus make a circuit twice tothe other train,while if going south or west he may shift it, say, four times, and thusmake the circuit to the other train a corresponding number of times.

Having described my invention, I claim- 1. In an electric signal system,the combination, with a track of a line of way, of a conductor extendingalong the line of way and insulated from said track; a vehicle movablealong said track; a source of electric energy; an electricalpole-changing switch connected to send current in either directionthrough the .indicator on said vehicle; circuit-controlling meansbetween-the source of energy and the two sides of/the indicator; atraveling current-collector carried by said vehicle and adapted to makecontact with said conductor; means for closing the circuit betweentheconductor and the track at a point distant from the vehicle; and avisual electrical indicator carried by said vehicle and in circuit withsaid current-collector and responsive to every variation in the length,and hence in the re sistance, of the conductor between said vehicle andsuch distant point,within the range of the indicator, and having anindicatorhand movable at either side of a normal, idle, centralposition, in accordance with the direction of movement of the vehicle,and adapted to indicate every variation in the distance between thevehicle and such distant point, as

the former approaches the latter, and also to show changes in thedirection of movement of the vehicle. V

2. In an electricsignal system, the combination, with a track of a lineof way, of a conductorextending along the line of way and insulated fromsaid track; vehicles movable along said track; travelingcurrent-collectors carried by said vehicles and adapted to make contactwith said conductor; a source of electric energy for each vehicle;electrical'polechanging switches connected to send current in eitherdirection through the indicators on said respective vehicles;circuit-controlling meansbetween the source of energy and the two sidesof the indicator on-each vehicle; and visual electrical indicatorscarried by said vehicles and in circuit, respectively,with saidcurrentcollectors and responsive to everyvariation in the length, andhence in the resistance, of the conductor between said vehicles, withinthe range of such indicators, and each having an indicator-hand movableat either side of a normal, idle, central position,-in accordance withthe direction of movement of the vehicle and adapted to indicate everyvariation in the distance between said vehicles and also to show changesin the direction of movement of each vehicle.

3. Inan electric signal system, the combination,with a'track of a lineofway, of a conductor extending along the line of way and insulated fromsaid track; vehicles movable along such track; automatically-reversibletraveling current-collectors carried by said vehicles and adapted tomake traveling contact-with said conductor and automatically reversibleby the reversal of the movements of said vehicles; a source of electricenergy connected to send current in either direction through theindicators on said respective vehicles; visual electrical indicatorscarried by said vehicles and in circuit, respectively,with saidcurrent-collectors and adapted to indicate the direction of movement ofsaid vehicles; and pole-changing switches carried-by said currentcollectors and. controlling the circuits through the indicators.

4. 'Thecombination, with a track of a line of way, of a conductorextending along the line of way and insulated from said track; a sourceof electric energy; a vehicle movable along said'track and acurrent-collector automatically reversible, while in contactwith saidconductor, by the reversal of the movement of the vehicle, andcomprising a carrierarm pivotally connected with the vehicle, and atriangular sliding contact-shoe pivoted to said carrier-arm andreversible, on the reversal of the movements of the vehicle, to

bring-its different sides into engagement with the conductor.

5. The combination,'with a track of a line of way, of a conductorextending along the line of Way and insulated from said track; a sourceof electric energy; a vehicle movable along said track; a spring-pressedcarrier pivotally connected with the vehicle; and anautomatically-reversible current-collector trailing at an acute angle tothe conductor while in contact therewith, and reversible to an oppositetrailing position, while in contact with said conductor, by the reversalof the movement of the vehicle, and comprising a springpressedcarrier-arm pivotally secured to said carrier and a contact-makerpivoted to said carrier-arm and movable therewith toward and from thevehicle and said conductor.

6. In an electric signal system, the combination, with a track of a lineof way, of a conductor extending along the line of way and insulatedfrom said track; a vehicle movable along such track; a signaling deviceon said vehicle; a source of electric energy connected to send currentin either direction through said signaling device; anautomatically-rcversible traveling current-collector carried by, andcontrolled by the reversal of the movement of, said vehicle and adaptedto make traveling contact with said conductor; and an automaticpole-ehan gin g switch controlled by the current-collector andcontrolling the direction of [low of the current through said signalingdevice.

7. In an electric signal system, the combination, with a track of a lineof way, of a conductor extending along the line of way and insulatedfrom said track; a vehicle movable along such track; a signaling deviceon said vehicle; a source of electric energy connected to send currentin either direction through said signaling device; anautomatically-reversible traveling current-collector carried by, andcontrolled by the reversal of the movement of, said vehicle and adaptedto make traveling contact with said conductor; and an automaticpole-changing switch carried by, and reversible with, thecurrent-collector and controlling the direction of flow of the currentthrough said signaling device.

8. In an electric signal system, the combination, with a track of a lineof way, of a cond uctor extending along the line of way and insulatedfrom said track; a traveling currentcollector carried by said vehicleand adapted to make traveling contact with said conductor; means forclosing the circuit between the conductor and the track at a pointdistant from the vehicle; a source of electric energy; a pair of relaysconnected in a norm ally-closed local circuit with the source of energy,and also connected with opposite sides of the main circuit, andoppositely operative, on the passage of a current through either side ofthe main line, to send current in a corresponding direction through theindicator on the vehiele; eircuit-controlling means between the sourceof energy and the relays; and a visual electrical indicator carried bysaid vehicle and in circuit with said current collector and adapted toindicate variations in the distance between the vehicle and such point.

LOUIS C. \VERNER.

itnesses:

FRED. J. DOLE, \VM. II. BLoDoETT.

